Re: "I want bigger sparks!" (me too!)

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "S.Gaeta by way of Terry Fritz <twftesla-at-qwest-dot-net>" <sgtporky-at-prodigy-dot-net>

Peter,

I have a 34 AWG, 3.5" by 13" secondary that I normally use with a .03 uf
cap,11 primary turns, and a 5/60 NST. This produces 15" streamers. If you
want a pleasant suprise with small coils like this try going up in current
instead of voltage. I think best results with mine will be had with 7.5 KV
at 60mA. I tried an experiment before all this putrid weather arrived. I
wound a new test primary of 21 turns total. I wanted to try different
capacitances, and voltages to see what the best performance was that I could
get out of that secondary. Best results were obtained with 6KV at 60 mA. I
got about 17", and that was with a lousy  gap with no air movement. I tried
9 KV at 60 mA and the coil went nuts!! It hit the primary of my larger coil
which was 21 inches away. After moving my bigger coil, I  ran it for another
4 minutes, but then it really started misbehaving. Immediately after it hit
its own primary, I got a huge racing spark down the whole length of the
secondary. At that point I shut it down right away. I haven't tried 7.5 KV
yet, but I feel that it will probably be the optimal one. I am going to try
a better static gap, and I also want to try a tiny rotary (not built yet)
with this coil. I feel that John's suggestion of raising the torroid will
help in this case too.
----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Friday, August 10, 2001 3:59 PM
Subject: Re: "I want bigger sparks!" (me too)


Original poster: "Peter Lawrence by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<Peter.Lawrence-at-Sun-dot-com>

*Snip*
If anyone else does better on a coil that is only 12" high I'ld like to know
how also!!!

It is suprising that you guys only get 12" sparks with 12 and 15 kv NSTs
while I get that with 9kv. I've been putting off trying larger NSTs because
I've been expecting to then have to build a long rod to remotely tune my
SG spacing 'cause I like to do this while the TC is running.

I've seen my sparks go from ~6" on 6-30 NST, 8~9" on 7.5-30 NST, to 10~12"
on 9-30 NST, so I expect the trend to continue, but perhaps as your
experience
shows it might level off instead.

-Peter Lawrence.

(ps, since I burned out my 7.5-30 NST I ALWAYS use a safety gap, and my
spark
length measurments are based on having a safety gap set appropriately for
the
NST voltage).